The subject matter herein relates generally to cable assemblies, and more particularly to cable assemblies for connector systems.
Some connector systems, such as network switches or computer servers with switching capability, include large backplanes with several switch cards and line cards plugged into the backplane. Generally, the line cards bring data from external sources into the system. The switch cards contain circuitry that may switch data from one line to another. Traces in the backplane interconnect the line cards and the appropriate switch cards. Other connector systems utilize midplanes to interconnect several switch cards and line cards plugged into the midplane. The midplane includes a printed circuit board to which the switch cards and line cards are connected. The midplane provides connectors on both sides of the circuit board, allowing daughter cards, such as the switch cards and line cards, to be connected on both sides of the midplane. The midplane circuit board provides conductive paths between the line cards and the switch cards.
Some signal loss is inherent in a trace through the midplane circuit board. As the number of card connections increase, more traces are required in the backplane or the midplane. The increased number of traces and the length of the traces introduce more and more signal loss, particularly at higher signal speeds.
Additionally, most connector systems provide for the connection of multiple connectors from the switch card or line card to the backplane or midplane at one time. Alignment of the connectors is problematic. Holding the connectors on the circuit boards within tight tolerances increases the cost of the connector system.
Furthermore, some connector systems define standard pass through connector systems, in which a plurality of connectors are provided on the backplane or the midplane, and the line cards and switch cards are plugged into the midplane in parallel orientations (e.g., both horizontal orientation or both vertical orientation). Other connector systems utilize inverted pass through connectors, wherein the connectors on one side of the midplane are oriented 180° with respect to the connectors on the opposite side of the midplane. The line cards and the switch cards are both plugged in, in the same orientation (e.g., a horizontal orientation or a vertical orientation), however the line cards and the switch cards may be offset due to the inverted orientations of the connectors. Other connector systems define orthogonal midplane connector systems, in which the connectors on one side of the midplane are oriented at 90° or 270° with respect to the connectors on other side of the midplane. Typically, different types of electrical connectors are designed for each of the connector systems, which increases the overall cost of the connector system. The different types electrical connectors for use in the midplane connector system generally degrades high speed signals passed therethrough due to discontinuities and the asymmetric nature of the connector configuration. Additionally, the complex design of the connectors, particularly with the connectors used in orthogonal midplane applications, increase the overall cost of the connector system.
Moreover, midplane connectors systems typically have a midplane circuit board positioned between the electrical connectors on opposite sides of the midplane circuit board. The midplane circuit board restricts airflow from one side of the circuit board to the other side of the circuit board. With high speed connector systems, the temperature of the components used in the connector system are typically higher, and heat dissipation from such components heretofore has proven difficult.
A need remains for a midplane connector system that is cost effective and reliable. A need remains for a midplane connector system for use in high speed signal applications, such as connector systems capable supporting 25 GB and higher signal speeds. A need remains a connector system that provides adequate heat dissipation from the components of the overall system.